Problem: $ { \left[\begin{array}{rr}{-2} & {2} \\ {1} & {1}\end{array}\right]+\left[\begin{array}{rr}{2} & {1} \\ {0} & {0}\end{array}\right] = {?} } $
Answer: To find the sum of two matrices, add the corresponding items between each matrix. ${\left[\begin{array}{rr}{-2}+{2} & {2}+{1} \\ {1}+{0} & {1}+{0}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rr}{0} & {3} \\ {1} & {1}\end{array}\right]}$